Heparanase up-regulation in tongue cancer - Tissue and saliva analysis

BACKGROUND. Heparanase up-regulation has been correlated with reduced postoperative survival in various cancers. METHODS. Heparanase expression was analyzed in 60 consenting tongue (mobile) cancer patients by means of immunohistochemistry. Heparanase levels were also analyzed in the saliva of both healthy controls and tongue cancer patients using a novel heparanase enzyme-linked immunosorbent assay method. RESULTS. Heparanase staining was positive (>0) in 92% and negative (=0) in 8% of the tumors and staining intensity correlated with tumor size and tumor stage. Moreover, the survival probability of patients negative for heparanase (=0) at 60 months was 100%, compared with only 41% for patients positive for heparanase (>O), suggesting that heparanase may serve as a prognostic factor for this malignancy and an attractive target for anticancer drug development. Heparanase was detected in the saliva of healthy controls and the mean concentration was determined as 119 +/- 37 pg/mL. Importantly, a nearly 3-fold increase of heparanase levels was detected in saliva collected from tongue cancer patients (334 +/- 69 pg/mQ, a difference that is statistically highly significant (P =.004). CONCLUSIONS. These findings support heparanase up-regulation in tongue cancer and raise the possibility of using this simple test as a diagnostic tool to monitor tongue cancer progression and response to treatment.